You will be really over the moon when you visit my hometown, but it often rains cats and dogs. I only go there once in a blue moon. IELTS Coaching in East Delhi. If you go, you will really hit the nail on the head. This is an extreme example, but it would surprise you how often students try to insert idioms at this rate. Again, there is no fixed rule as to how often you should use them, but as a general rule use them sparingly, ironically a good idiom to remind you of this is 'remember, less is more'.

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